Controversial vapor shops are becoming more popular in the Sacramento region and across the nation. Sales of electronic cigarettes are expected to reach $1 billion this year. KCRA 3's Tom DuHain reports on the matter, and says medical professionals have a warning for users.

TOM DUHAIN REPORTS THAT MEDICAL PROFESSIONALS HAVE A WARNING FOR USERS. IT IS INCREASINGLY COMMON TO SEE THIS. PEOPLE THINKING AND SMOKING ELECTRONIC CIGARETTES THAT PROVES A TOBACCO-THREE BIT PER PRODUCES NICOTINE -- VAPOR THAT PRODUCES NICOTINE. IT IS NICOTINE AND FLAVORED GLYCOL. THERE ARE 150 FLAVORS. WHEN THE STORE OPENED, ONLY A HANDFUL OF PAPER RETAILERS. NOW, TO DOZENS IN THE REGION. -- TWO DO ZEN IN THE REGION. IT WORKS. PLANET OF THE VAPES HAS TWO SHOPS. THERE ARE COMPETITIONS. YOU KNOW? COMPETITION IS GROWING AND MANY ARE HOPING TO QUIT SMOKING TOBACCO. MEDICAL EXPERTS SAY IT IS NOT SAFE. IT HAS NICOTINE, AN ADDICTIVE PRODUCT. THIS PERSON SAYS THAT THE NICOTINE JUICE IS A TOBACCO PRODUCT. UNLESS THEY GET OFF, THEY ARE STILL SMOKERS. IT IS FLOURISHING.